The present invention generally relates to surgical access devices for entering a patient's body, and in particular to visual insufflation obturators providing a visual and gaseous pathway.
Laparoscopic surgery of the abdominal area typically requires the introduction of an insufflation gas into the peritoneal cavity of the patient. The insufflation gas is usually pressurized to about 10 mm Hg above atmospheric pressure. This in turn lifts the abdominal wall away from the organs underlying it. Cannulas having seals are then placed at various locations through the abdominal wall to allow the use of a laparoscope and operating instruments. It is well known that establishing access to a non-inflated peritoneal cavity can be a very dangerous part of any laparoscopic procedure. The most common method to achieve insufflation is to pass a sharp needle through the abdominal wall and into the abdominal region, and then inject a gas through the needle and into the region thereby creating an enlarged or ballooned cavity to accommodate a laparoscopic procedure. Unfortunately, insertion of the needle has been required without any visual aid to facilitate location of the sharp needlepoint.
In order to reduce the probability of inadvertent penetration of delicate internal organs in this “blind” procedure, the sharp insufflation needle has been provided with a blunt or rounded member disposed within the lumen of the needle, and biased by a spring to an extended position beyond the needle tip. A drawback of this “blind” insertion is the surgeon may inadvertently contact the organs and tissues underlying the abdominal wall such as major blood vessels and the intestinal tract. Once access is gained, it can take several minutes for the gas to insufflate the abdomen and while this is happening the surgeon may be unaware of any complications caused by the insertion of the needle.
The Hasson technique can also be used to gain initial access to the peritoneal cavity. This technique involves making a mini-laparotomy and using the fingers to bluntly dissect the tissues of the abdominal wall and thereby creating an access similar to an open surgical procedure. Although generally considered less complicated, it can result in an access site that is not well suited for the subsequent introduction and use of a laparoscopic cannula. The cannula is typically held in place with an additional device that allows the cannula to be tied down with sutures to prevent it from slipping out of the abdominal wall. This may also leave a large defect and is difficult to perform in large abdominal walls.
Some surgeons have used trocar cannulas with an obturator for the initial entry into the peritoneal cavity. However, in order to allow the subsequent introduction of insufflation gas through the cannula, the trocar cannula must be inserted all the way through the wall of the abdomen and this in turn can be potentially dangerous as the tip of the trocar may have to advance as much as one inch beyond the distal surface of the abdominal wall and into the underlying anatomical structures. Additionally, the obturator must thereafter be removed in order to allow the introduction of the insufflation gas. As such, there remains a need in the art for an improved surgical instrument that provides enhanced visual entry and visual insufflation that minimizes the risks to organs, tissues and vessels underlying a body wall.